Line graphs, the mean and pie charts · Usually met around P6
Drawing a line graph
In time order: plot each point, then join them.
How to do it
Method
In time order: plot each point, then join them
From 16, 2 a square: 26 goes 5 squares up
Another way
Read it back
16 + 5 × 2 = 26
In full
To draw a line graph from a table: along the bottom, the items in time order (Monday, Tuesday…); up the side, the amounts. Look at the biggest number first and choose what each square stands for so that it fits: biggest 30, 2 a square, needs 30 ÷ 2 = 15 squares. If the side doesn't start at 0 but at, say, 16, then 26 goes (26 − 16) ÷ 2 = 5 squares up. Plot each point, then join them left to right with straight lines. Check: read each point back and match it with the table; the order mustn't be mixed up.
Worked examples
Have a go first, then open each one for the answer and the working.
Example 1
Drawing a line graph, the side starts at 0 and each square stands for 10. How many squares up does the point for 20 go?
Show the answer and working
Answer: 2 squares
20 ÷ 10 = 2.
Example 2
The biggest number in the table is 248. The side of the line graph starts at 0 with 50 a square. At least how many squares tall must it be?
Show the answer and working
Answer: 5 squares
248 ÷ 50 isn't whole, so round up: 5 squares fit it.
Example 3
The highest temperatures from Monday to Thursday were 32°C, 30°C, 22°C and 22°C. This line graph shows them correctly.
True or false?
Show the answer and working
Answer: False
Read each point back: the side starts at 16, 2°C a square; every point must match the table.
Practise it in the game →Line graphs, the mean and pie charts · Free to start, unlimited questions, no download